For certain kinds of products, it is particularly important to protect against physical tampering after the product has been sold or distributed to an end user. For example, tampering is of particular concern for certain types of electronic devices, such as devices that store or process private information, or devices that individuals may be tempted to “hack” in order to use functions and capabilities that they are not authorized to use.
A conventional technique for detecting tampering in an electronic device is to enshroud the sensitive components within the device with a wire mesh that is disposed on a flexible substrate. The wire mesh is connected to an electrical power source and to a detector within the device. Typically such a wire mesh enshrouds a single circuit board. The mesh fits loosely around the entire circuit board, such that any attempt to physically access the components on the circuit board will likely damage the mesh to the extent of causing an open circuit condition in the mesh. The detector detects this condition and can trigger an appropriate countermeasure in response.
While a flexible mesh such as described above provides some degree of tampering protection, it is not impossible for a determined wrongdoer to circumvent it. Further, it is possible to open the electronic device without necessarily damaging the mesh, and therefore, without necessarily triggering anti-tampering countermeasures. Additionally, the wire mesh adds to the overall cost of the device.